Do you have adequate searching skills?
by Robert Joven, MLS
Information & Education Services Librarian

A Johns Hopkins panel investigating the June 2001 death of a volunteer
in a Johns Hopkins University asthma study concluded that the principal
researcher may have neglected to do a thorough search of the literature
on the drug hexamethonium before the drug was used in a clinical investigation.
The researcher searched PubMed, which indexes articles back to 1966, as
well as a limited number of other resources, but missed earlier reports
of the drug's toxicity. Medical journal articles published in the 1950s
(not available in Pubmed) apparently warned of lung damage caused by hexamethonium.
(See http://www.hopkinsmedicine.org/researchvolunteerdeath.html)
Both clinical and administrative errors may have been made during this
asthma study. The initial inadequate search of the medical literature,
however, probably laid the groundwork for tragedy. It is this aspect of
the case that concerns medical librarians. The limited number of resources
used by the Johns Hopkins searcher impaired the comprehensiveness, or
exhaustive nature, of the search. Inadequate searching skills can pose
another kind of obstacle to a good literature search by compromising the
refinement, or depth, of the search.

What can be done to ensure that a literature search is,
at the very least, sufficient for patient safety? Knowing what resources
are available and an adequate searching skill are the key ingredients
to a successful literature search.

Medline, covering approximately 4300 biomedical journals
from 1966 to the present is an excellent place to start searching. However,
Medline should not be considered the endpoint of comprehensive literature
searching. Medline’s journal coverage is extensive but it represents
only a portion of the number of biomedical journals published worldwide.
Other databases such as Web of Science, Biological Abstracts, Chemical
Abstracts, PsycInfo are considered valuable resources other than Medline.

Prior to 1966, OLDMEDLINE is available through the NLM
Gateway at http://gateway.nlm.nih.gov.
It contains citations from 1957-1965. More details about these earlier
online citations may be found athttp://www.nlm.nih.gov/services/oldmed.html
Prior to 1957 there is NO online source from the National Library of Medicine.
To cover prior years of medical literature, the print Index Medicus and
other print sources must be searched manually. We all know it is convenient
to do a literature search from a computer. However, the researcher should
never discount the use of print resources. The accumulated knowledge of
prior years is not always available at the click of a mouse. Libraries
still house and maintain valuable print resources. These print sources
may have no electronic equivalents.

It is probable that the principal researcher in the Johns
Hopkins case acted in good faith in his search of the literature. But
he may have lacked an understanding of the complexity of literature searching
as well as the more advanced searching skills necessary to perform adequately
on his own. Those who are fairly new to searching, or unaware of a database's
advanced features, may be easily satisfied with their first results. Librarians,
who have several years of daily experience with database searching, still
have to take time and thought when formulating a search strategy. The
competent use of MeSH (Medical Subject Headings) vocabulary and subheadings
is essential to a thorough search in the MEDLINE database.

It is important to realize that when in doubt, or if
any concerns arise about the completeness of your information when doing
a literature search, you must contact a medical librarian. They offer
many services to help conduct an adequate literature search. They have
the knowledge and the expertise to search different databases to ensure
an effective literature search.

The Information and Education Services Department at the Lyman Maynard
Stowe Library provide different types of instructions to help you improve
your searching skills depending on your need. We offer a regularly scheduled
monthly library classes, a one-on-one 30-minute consultation, and specialized
database instruction for individuals or groups upon request. These services
are free to the faculty, staff, and students of the Health Center. We
also offer a Mediated Database Searching service. These searches, performed
by the Information and Education Services Librarian, are available for
a fee. If you have any questions regarding any of these services, or to
schedule a session with a librarian, please call us at 679-4051 or send
us an e-mail at ref@nso.uchc.edu.